Crystal Structure and Hirshfeld Surface Analysis of Bis(3-thienoyl) Disulfide

The spectroscopic characterization (¹H, ¹³C{¹H} NMR, UV–Vis) and single-crystal X-ray diffraction (scXRD) analysis accomplished by inspection of the Hirshfeld surface of bis(3-thienoyl) disulfide (1) is described. The title compound 1 crystallizes in the monoclinic space group P2₁/n. The unit cell parameters are a?=?7.9959(3) Å, b?=?6.4348(3) Å, c?=?22.4924(9) Å, β?=?100.108(4)°, V?=?1139.32(8) ų, Z?=?4, R_gt(F)?=?0.0278, wR_ref(F²)?=?0.0667. The packing of 1 is dominated by S?O and S?S interactions, giving a 2D layer structure parallel to (101). The X‐ray crystal structure analysis revealed the packing of 1 is dominated by S?O and S?S interactions, giving a 2D layer structure parallel to (101). The intermolecular interactions in 1 were analyzed using the Hirshfeld surface method including 2D fingerprint plots and enrichment ratios (E), which shows that the most favored intermolecular contacts are the O?H and C?S indicated by E values above 1.30. The interaction energies between molecular pairs revealed the importance of the weak O?H and C?S interactions in stabilizing the molecular structure of 1.

Graphic Abstract

Single crystal X-ray structure analysis, DFT calculations and Hirshfeld surface analysis to identify intermolecular interactions within the solid state structure of bis(3-thienoyl) disulfide (1).

     

Biphenyl derivatives

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NHC‐Catalyzed Asymmetric Synthesis of Functionalized Succinimides from Enals and α‐Ketoamides

The efficient asymmetric synthesis of highly substituted succinimides from α,β‐unsaturated aldehydes and α‐ketoamides via NHC‐catalyzed [3+2] cycloaddition has been developed. The new scalable protocol significantly expands the utility of NHC catalysis for the synthesis of heterocycles and provides easy access to assemble a wide range of succinimides from simple starting materials.     

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An investigation into the fracture behaviour of ethylene propylene impact copolymers

Injection moulded copolymer specimens containing between 6 to 11% ethylene were impacted using the drop weight method at 23°C and −20°C. Their response to the impact event was analysed in terms of failure mechanisms by considering their initiation and propagation energies at the respective temperatures. At −20°C, the results indicated that the multiple shear yielding toughening mechanism is predominant whereas room temperature tests show evidence of multiple crazing behaviour. The peak force sustained by the specimens decreased with the testing temperature.     

Anionic Oligothiophenes Compete for Binding of X‐34 but not PIB to Recombinant Aβ Amyloid Fibrils and Alzheimer's Disease Brain‐Derived Aβ

Deposits comprised of amyloid‐β (Aβ) are one of the pathological hallmarks of Alzheimer's disease (AD) and small hydrophobic ligands targeting these aggregated species are used clinically for the diagnosis of AD. Herein, we observed that anionic oligothiophenes efficiently displaced X‐34, a Congo Red analogue, but not Pittsburgh compound B (PIB) from recombinant Aβ amyloid fibrils and Alzheimer's disease brain‐derived Aβ. Overall, we foresee that the oligothiophene scaffold offers the possibility to develop novel high‐affinity ligands for Aβ pathology only found in human AD brain, targeting a different site than PIB.     

DNA-binding of semirigid binuclear ruthenium complex delta,delta-[mu-(11,11'-bidppz)(phen)(4)ru(2)](4+): extremely slow intercalation kinetics

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